15 research outputs found

    Skeletal Light-Scattering Accelerates Bleaching Response in Reef-Building Corals

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    Background At the forefront of ecosystems adversely affected by climate change, coral reefs are sensitive to anomalously high temperatures which disassociate (bleaching) photosynthetic symbionts (Symbiodinium) from coral hosts and cause increasingly frequent and severe mass mortality events. Susceptibility to bleaching and mortality is variable among corals, and is determined by unknown proportions of environmental history and the synergy of Symbiodinium- and coral-specific properties. Symbiodinium live within host tissues overlaying the coral skeleton, which increases light availability through multiple light-scattering, forming one of the most efficient biological collectors of solar radiation. Light-transport in the upper ~200 μm layer of corals skeletons (measured as ‘microscopic’ reduced-scattering coefficient, μ′S,m), has been identified as a determinant of excess light increase during bleaching and is therefore a potential determinant of the differential rate and severity of bleaching response among coral species. Results Here we experimentally demonstrate (in ten coral species) that, under thermal stress alone or combined thermal and light stress, low-μ′S,m corals bleach at higher rate and severity than high-μ′S,m corals and the Symbiodinium associated with low-μ′S,m corals experience twice the decrease in photochemical efficiency. We further modelled the light absorbed by Symbiodinium due to skeletal-scattering and show that the estimated skeleton-dependent light absorbed by Symbiodinium (per unit of photosynthetic pigment) and the temporal rate of increase in absorbed light during bleaching are several fold higher in low-μ′S,m corals. Conclusions While symbionts associated with low-μ′S,m corals receive less total light from the skeleton, they experience a higher rate of light increase once bleaching is initiated and absorbing bodies are lost; further precipitating the bleaching response. Because microscopic skeletal light-scattering is a robust predictor of light-dependent bleaching among the corals assessed here, this work establishes μ′S,m as one of the key determinants of differential bleaching response

    Is being overweight associated with engagement in self-injurious behaviours in adolescence, or do psychological factors have more “weight”?

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    Introduction The purpose of this study was to examine the prevalence of non-suicidal self-injurious behaviours (NSSI) among healthy weight and overweight adolescents and to examine the role of age, gender, weight status, treatment condition for weight control, and psychological variables (psychopathological symptoms and emotional skills) in the prediction of NSSI. Methods The study had a cross-sectional design, and participants (n = 370) were aged 14-19 years and were divided in three groups: 205 adolescents with normal weight, 82 adolescents from the community with overweight/obesity, and 83 adolescents with overweight/obesity and in outpatient treatment for weight control. Results The prevalence of these behaviours in the overweight community group (25.6 %) and in the overweight clinical group (14.5 %) was similar to their healthy weight peers (19 %). Not attending an outpatient treatment for weight control, higher psychopathology and less ability to regulate emotions predict the presence of NSSI. Conclusion Being overweight is not associated with NSSI, but psychosocial variables such as psychopathology, emotional deregulation and the absence of medical care predict these behaviours.info:eu-repo/semantics/publishedVersio

    Zastosowanie potencjometrycznej metody wykrywania pęknięć w procesie renowacji narzędzi kuźniczych

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    This article deals with renovation of tools for volume forming. It analyzes the current state of the solved problems of renovation of tools for volume forming and possibilities of rationalizations and cost reduction by using non-destructive detection technologies for examination of inside defects.Praca dotyczy renowacji narzędzi do obróbki objętościowej. Prowadzono analizę metod i zagadnień związanych z renowacją narzędzi do kształtowania objętościowego oraz możliwości ich racjonalizacji. Uwzględniono zmniejszenie kosztów przez zastosowanie metod nieniszczących do oceny wad wewnętrznych narzędzi

    Pandemic-related racial discrimination and its health impact among non-Indigenous racially minoritized peoples in high-income contexts : a systematic review

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    This study aims to review articles reporting the perspectives and experiences of pandemic-related discrimination among racially minoritized peoples in high-income contexts. We searched online databases (Medline, EMBASE, PsycINFO, Web of Science, and ProQuest) for peer-reviewed articles published between January 2002 and October 2020. Eligible studies reported either quantitative or qualitative accounts of pandemic-related discrimination from the perspectives of racially minoritized peoples in high-income contexts. Two authors screened 30% of titles/abstracts, and all full-text articles. Each article included for extraction underwent a quality assessment by two reviewers. Data were extracted and categorized thematically using NVivo 12, followed by a secondary analysis informed by critical race theory. Of the 1289 articles screened, 16 articles from five countries met the inclusion criteria. Racial discrimination is heightened during pandemic periods, due to the social association of specific racial groups with pandemic diseases including COVID-19, SARS (Asian), H1N1 (Hispanic) and Ebola (African). Fear based responses to racially minoritized peoples during pandemic periods included verbal/physical abuse, hypersurveillance, and avoidance, often occurring in public spaces. Pandemic-related racism had subsequent impacts on mental health and health care accessibility. Various coping strategies, including community support, avoidance, and problem solving, were documented in response to racial discrimination. Racialized discrimination and violence is a serious threat to the health and wellbeing of racially minoritized peoples, particularly due to its increase during pandemic periods. Racism must be recognized as a public health issue, and efforts to address its increased impact in pandemic contexts should be made, including ensuring that adequate representation of racially minoritized groups is present in policy, planning, and implementation

    Clinicians' Approach to Patent Foramen Ovale Closure after Stroke: Comparing Cardiologists and Neurologists

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    Background Evidence from randomized trials and updated professional society guidelines supports patent foramen ovale (PFO) closure after cryptogenic stroke in select patients. It is unclear how this has been integrated into real‐world practice, so we aimed to compare practice patterns between cardiologists and neurologists. Methods and Results In March of 2021, a survey of cardiologists and neurologists who work or previously trained at the University of Pennsylvania Health System assessed practice preferences with respect to PFO closure after stroke. Clinical vignettes isolated specific variables of interest and used a 5‐point Likert scale to assess the level of support for PFO closure. Stroke neurologists and interventional cardiologists were compared by Wilcoxon‐Mann–Whitney tests. Secondarily, Kruskal–Wallis tests compared stroke neurologists, general neurologists, interventional cardiologists, and general cardiologists. We received 106 responses from 182 survey recipients (31/31 stroke neurologists, 38/46 interventional cardiologists, 20/30 general neurologists, and 17/77 general cardiologists). A similar proportion of stroke neurologists and interventional cardiologists favored PFO closure in a young patient with cryptogenic stroke, 88% and 87%, respectively (P=0.54). Interventionalists were more likely than stroke neurologists to support closure in the context of an alternative high‐risk stroke mechanism, 14% and 0%, respectively (P=0.003). Stroke neurologists were more likely to oppose closure on the basis of older age (P=0.01). Conclusions There are key differences between how neurologists and cardiologists approach PFO closure after stroke, particularly when interpreting the stroke etiology and when considering closure beyond the scope of prior trials; this underscores the importance of collaboration between cardiologists and neurologists

    Descriptor Optimization for Multimedia Indexing and Retrieval

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    International audienceIn this paper, we propose and evaluate a method for optimizing descriptors used for content-based multimedia indexing and retrieval. A large variety of descriptors are commonly used for this purpose. However, the most efficient ones often have characteristics preventing them to be easily used in large scale systems. They may have very high dimensionality (up to tens of thousands dimensions) and/or be suited for a distance which is costly to compute (e.g. Chi square). The proposed method combines a PCA-based dimensionality reduction with pre- and post-PCA non-linear transformations. The resulting transformation is globally optimized. The produced descriptors have a much lower dimensionality while performing at least as well, and often significantly better, with the Euclidean distance than the original high dimensionality descriptors with their optimal distance. Our approach also includes a hyper-parameter optimization procedure based on the use of a fast kNN classifier and on a polynomial fit to overcome the MAP metric instability. The method has been validated and evaluated on a variety of descriptors using the TRECVid 2010 semantic indexing task data. It has then be applied at large scale for the TRECVid 2012 semantic indexing task on tens of descriptors of various types and with initial dimensionalities ranging from 15 up to 32,768. The same transformation can be used also for multimedia retrieval in the context of query by example and/or of relevance
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